COMLEX II: STATISTICS EXAM
QUESTIONS WITH VERIFIED ANSWERS
How do you calculate relative risk? - Correct Answers -[A/(A+B)]/[C/(C+D)]
expresses the risk of disease in people exposed to a given factor
What type of study uses relative risk to evaluate conclusions? - Correct Answers -cohort
study
what type of study uses odds ratio to evaluate conclusions? - Correct Answers -case-
control study
How do you calculate specificity? - Correct Answers -This is everyone w/o disease who
tested neg/everyone without the disease; D/B+D
What is positive predictive value? - Correct Answers -PPV is the probability that a
person who tested positive actually has the disease; A/A+B
What is negative predictive value? - Correct Answers -NPV is the probability that a
person who tested negative actually does not have the disease; D/C+D
Which is better: cohort study or case control? - Correct Answers -Cohort study is better
what is the difference between case-control and cohort studies? - Correct Answers -
cohort study: examines a group of subjects exposed to a given situation or factor;
usually prospective
case-control: retrospective comparison of patients with a disease to healthy controls;
frequency of certain exposures in both groups is considered
How do you calculate the odds ratio? - Correct Answers -(A/B)/(C/D)
expresses the odds of exposure among patients with a disease compared with odds of
exposure among patients wo a disease
What does an RR val of 1 mean? - Correct Answers -RR = 1 means that there is NO
relationship between exposure and disease
What does RR <1 mean? - Correct Answers -RR <1 suggests a negative relationship
between exposure and disease (exposure prevents disease)
QUESTIONS WITH VERIFIED ANSWERS
How do you calculate relative risk? - Correct Answers -[A/(A+B)]/[C/(C+D)]
expresses the risk of disease in people exposed to a given factor
What type of study uses relative risk to evaluate conclusions? - Correct Answers -cohort
study
what type of study uses odds ratio to evaluate conclusions? - Correct Answers -case-
control study
How do you calculate specificity? - Correct Answers -This is everyone w/o disease who
tested neg/everyone without the disease; D/B+D
What is positive predictive value? - Correct Answers -PPV is the probability that a
person who tested positive actually has the disease; A/A+B
What is negative predictive value? - Correct Answers -NPV is the probability that a
person who tested negative actually does not have the disease; D/C+D
Which is better: cohort study or case control? - Correct Answers -Cohort study is better
what is the difference between case-control and cohort studies? - Correct Answers -
cohort study: examines a group of subjects exposed to a given situation or factor;
usually prospective
case-control: retrospective comparison of patients with a disease to healthy controls;
frequency of certain exposures in both groups is considered
How do you calculate the odds ratio? - Correct Answers -(A/B)/(C/D)
expresses the odds of exposure among patients with a disease compared with odds of
exposure among patients wo a disease
What does an RR val of 1 mean? - Correct Answers -RR = 1 means that there is NO
relationship between exposure and disease
What does RR <1 mean? - Correct Answers -RR <1 suggests a negative relationship
between exposure and disease (exposure prevents disease)
